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How to Navigate WPC's PQPF and Percentile QPF Web Pages

 
For those of you visiting this page for the first time, the following provides an introduction to the user interface. One way to view the interface is to break it up into four sections. These are the tab bar, the main menu bar, viewing options, and finally the forecast display window.  If you are interested in information about the products themselves, please visit the page About WPC's Probabilistic QPF products.
 
At the top is a tab bar (shown below) displaying the two main product options.

This is the tab bar containing the options to view probabilistic QPFs and percentile QPFs.

Clicking on a tab will take you to a main page displaying that product type. Note that the currently selected tab will display in a darker blue (in the case above, you are viewing the "Probability of Precipitation of at Least a Specific Amount" guidance).
 

Probability of Precipitation of at Least a Specific Amount
 
If you choose to view this guidance, a menu bar similar to the following will display below the tabs.

Displays the precipitation amount, valid forecast time range of the entire product suite, 
    and a timeline with product valid times. 
    Mouse over the valid time to view the forecast in the main window below it, or click the valid time to view a larger image.

The menu bar displays the precipitation amount (in the case above, ≥ 0.01"), the valid forecast period for the entire product suite, and a timeline with product valid times and dates. There are two ways to use the timeline to access a forecast. Moving the mouse over a given period (such as 18Z Apr 02) will change that cell to a lighter blue and show in the main window the 6-hour probability of precipitation ending at the displayed time. (i.e. in the above example, the 6-hour probability of precipitation exceeding 0.01" is valid from 12Z-18Z Apr 02.) If you click on the link in the timeline, a larger, printable version of the forecast will display.
 
To the right of the menu bar (and displayed below) are options to change the forecast display.  You can view precipitation probabilities for different amounts (ranging from 0.01" to 3.00") OR view all of the precipitation amounts valid at a selected forecast time. Note that the menu bar will be combined into a single column rather than split as seen below.
  The menu showing the different precipitation amount options
          for which probabilities are calculated. Click to select an amount. The menu showing the valid ending times of the 6-hour forecasts.
          Click to view the probabilities of precipitation for each amount valid at the selected time.  
 
Choosing a different precipitation amount will display a menu bar similar to that at the start of this section, but show the probability of precipitation exceeding the newly chosen amount for each 6-hour period.  Choosing a particular valid time will result in different menu bar (shown below).  Similar to the forecast period timeline, either mouse over a precipitation amount to view the forecast in the main window or click on the amount to bring up a larger, printable version of the forecast.

A menu bar displaying the full 6-hour valid period and all PQPF thresholds.  Mouse over a threshold 
  to view the forecast in the main window, or click the threshold to view a larger image.
 

 
Below is an example of the main display for the 6-hour probability of precipitation exceeding a specified amount.
 
Example of the main display area for the 6-hour 
   probability of precipitation exceeding a specified amount.
 

 
Precipitation Amount by Percentile
 
If you choose to view precipitation amounts broken down by percentile, a menu bar similar to the following will display below the tabs.

Displays the percentile, valid forecast time range of the entire product suite, and a timeline with 
    product valid times.  Mouse over the valid time to view the forecast in the main window below it, or click the valid time to view a larger image.

This format and navigation is identical to the 6-hour Probability of precipitation menu bar, except that at the top, the QPF percentile is displayed. The default when initially opening this web page is the 50th percentile.
 
To the right of the menu bar (and displayed to the right) are options to change the forecast display.  You can view different QPF percentiles (ranging from the 5th through the 95th...the default is the 50th percentile) OR view all of the QPF percentiles valid at a selected forecast time. Note that the menu bar will be combined into a single column rather than split as seen below.
  The menu showing the different QPF percentile options.
          Click to select a percentile. The menu showing the valid ending times of the 6-hour forecasts. 
          Click to view all percentiles valid at the selected time.  
 
Choosing a different percentile will result in a menu bar similar to that at the start of this section, but with a different percentile value. Choosing a particular valid time will result in a different menu bar (shown below). Similar to the forecast period timeline, either mouse over a percentile to view the forecast in the main window or click on the percentile to bring up a larger, printable version of the forecast.

A menu bar displaying the full 6-hour valid period and all QPF percentiles.  Mouse over a percentile
  to view the forecast in the main window, or click the percentile to view a larger image.
 

 
Below is an example of the main display area for the 6-hour precipitation amounts by percentile.
 
Example of the main display area for the 6-hour precipitation amounts by percentile.
 

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Page last modified: Thursday, 19-May-2022 21:31:33 UTC